January 10, 2008
Diagnosis and Symptoms, Insulin
Question from Sherman Oaks, California, USA:
My three and a half-year-old, diagnosed in January 2007, has had quite a ride since diagnosis. We have never been able to get him stable for any more than a few days at a time. He went on a pump in July and we still have chronic control problems. A few weeks ago, he went from his average insulin requirement of approximately 12 units a day down to almost nothing. It lasted for almost two weeks, then, last week, he went back up to needing the almost 12 units. He has been running high for the week as we try to re-adjust his pump back up, and then again last night, I had to drastically reduce his insulin while giving him lots of carbohydrates, without insulin, just to keep his blood sugar around 70 mg/dl [3.9 mmol/L]. Today, we started the day as usual believing the through-the-night period was just an "off" night, but he dropped to 40 mg/dl [2.2 mmol/L] after breakfast, very reminiscent of what happened a few weeks ago when I had to disconnect his pump. It has taken more than 50 grams of carbohydrates today (without insulin) to keep him up plus his basal is set at 50% of his normal rate of only 0.25. He is barely getting any insulin. Has anyone else every experienced this? He is not sick. He wasn't sick a few weeks ago either. The doctor says it is very unusual and thinks we should consider hospitalizing him for further evaluation. I wonder if he was misdiagnosed or "missed" diagnosed - maybe he has a different kind of diabetes. Can this happen with MODY or type 2 or that type 1.5 I have read about? Could he have something else primary related to his liver, pancreas or thyroid or something that has caused a secondary diabetes condition, thus the fluctuating "diabetes?" What can cause things that look like diabetes or what can cause someone to not need insulin all of a sudden and for a long period of time? What kind of doctor should we seek that will look outside of the box?
What you describe is extremely rare. It makes one want to look for other causes as you suggest. Adrenal, thyroid, celiac diagnoses sometimes will cause such problems but this off and on cycling does not quite fit anything else. Intermittent excess insulin coming from his own pancreas would also be extremely rare and there are blood tests that could detect this when he is in hypoglycemic phase. Other antibodies may also come and go erratically and these might be able to be measured, but this is a difficult task. MODY should not do this, however. There are excellent pediatric diabetes folks in the Los Angeles area who should be able to problem solve with you. I might agree with an in-patient evaluation, particularly with an admission when you notice something odd about insulin requirements. Using a CGMS may also be helpful since you would be “alarmed” and might be able to respond more quickly to quickly changing insulin requirements. For sure, I would ask for a consultation visit with your pediatric diabetes team and see what everyone thinks is the next step.